The product is a study guide titled "NASA SP-7012 The International System Of Units 2nd Revision 1973 E. A Mechtly PB" published by NASA in 1973. Written by E. A. Mechtly, this guide is focused on the International System of Units and provides detailed information on the topic. It is a valuable resource for students and professionals interested in understanding the units of measurement used in various fields, particularly in the context of space exploration and research conducted by NASA.